External Alarms Connections; Master-Slave Operation; Alarms In And Alarms Out Connections - Cisco Prisma II Hybrid Amplifier Installation Manual

External Alarms Connections

Master-Slave Operation

All Prisma II modules ship from the factory configured as a "master." They can be
reconfigured as "slave" or redundant modules through command line interface (CLI)
commands. The chassis allows for local hard-wired redundancy by using the
ALARM IN and ALARM OUT connectors on the connector interface panel. With
these connectors, a master-slave pair of modules can be configured so that if the
master fails, the slave takes over.

ALARMS IN and ALARMS OUT Connections

The chassis provides two connections for external alarms to and from each module
slot. These alarm connections are located in two 37-pin D-connectors (DB-37) labeled
ALARMS IN and ALARMS OUT.
When a critical alarm occurs in a master module, the master turns off and the slave
(redundant module) is enabled. To make this happen, the pin representing the
master module slot in the ALARM OUT connector must be externally wired to the
pin representing the slave module slot in the ALARM IN connector.
Important:
This module takes up two slots in the Prisma II chassis. For purposes of

redundancy wiring, the module is identified with the higher-numbered slot. For
example, if the module occupies slots 6 and 7 (module ejector lever at slot 6), its
ALARM IN and ALARM OUT connections are made at slot 7, and the pins for
slot 6 are not used.
Any device configured as a master ignores its own ALARM IN contacts.

To verify proper wiring and redundant configuration, unplug the master device

and confirm that the slave module turns on as a result.
Once the ALARM IN and ALARM OUT contacts are wired, take care to ensure

that the master and slave modules are not moved to other slots. If they are, the
ALARM IN and ALARM OUT connectors will need to be rewired to the
appropriate pins.
78-4025693-01 Rev D

External Alarms Connections

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